How To Remove, Clear, Reveal, Unlock or Reset BIOS Security Password

Any amateur computer technician should know how to reset BIOS passwords that can be setup from within the BIOS because there are times when they need access to change some configuration options such as the boot order or disable functions like AHCI mode. If a password has been set, you cannot enter the BIOS or sometimes even boot the computer itself unless you know it, and this can be a real headache if nobody knows what the password is. It’s becoming increasingly common due to the amount of computers changing hands these days and previous owners have set a password and not passed on that information.

The most common way that most of us know for resetting or clearing the BIOS password is to physically remove the power from the computer by disconnecting all cables and removing the battery from the motherboard for a few minutes. Another way is to short the clear CMOS jumper on the motherboard itself if one is present. These methods work because on most desktop and a few laptop motherboards, a battery is used to sustain the BIOS/CMOS settings. By cutting off the power, the BIOS/CMOS settings and password will be erased.

If for some reason you’re unable to reset the computer’s BIOS security password by removing the battery or clearing the CMOS jumper, and you don’t know what the password is, here are several options which you can try out to clear it.

Generic Backdoor Default Passwords

Before using any tools that try to reset or make changes to your BIOS, it’s worth seeing if any of the well known backdoor or default passwords that have been around for some time work. Click on the link below to view the list, the passwords are case sensitive.

If you can Boot into Windows

CMOS De-Animator is an up to date tool compared to the majority of BIOS hacking/resetting tools out there, and can reset the BIOS password from within Windows. The latest version 2 executable of CMOS De-Animator is compatible with both 32-bit and 64-bit operating systems.

All you need to do is run the tool as administrator (right click -> “Run as administrator”) and click the Proceed button followed by restarting the computer. When your computer boots up, you should see a CMOS checksum error where it allows you to access the BIOS without a password. CMOS De-Animator works by invalidating the checksum of your system’s CMOS memory which resets all settings to default and clears any stored BIOS passwords upon reboot.

CMOS De-Animator also has a basic backup and restore option to give you that extra little bit of added security, the file will be stored with a .dea extension. Do take note of the authors warnings about the problematic nature of using the program on laptops and that usage of CMOS De-Animator is at your own risk. Because of its nature the program will sometimes trigger false positives in antivirus software and on sites like Virus Total.

If you Cannot Boot From Hard Drive or CD

Although disconnecting the power and removing the battery from the motherboard on desktop computers for a few minutes should remove the password, this is much less likely to work on laptops, but it’s still possible on some older models. For extra security the passwords for laptops are usually stored on a separate EEPROM chip which doesn’t rely on the BIOS battery and is unaffected by cutting the power.

If you enter the wrong password a few times on a laptop, there will be a message that the laptop is locked. You will be presented with something like a “System Disabled” or “Password check failed. System Halted” message with some numbers. If this message appears while entering the BIOS you can simply power off and on the computer to remove it and try again. Take note of the number because it’s a valuable piece of information and required to generate the BIOS backdoor password to get back into the laptop.

All you need to do is to have the number to hand and then visit the BIOS Master Password Generator webpage. This website has been setup to let you easily get the possible passwords based on the number entered, simply enter it and press the button. Then look at the results and note all the passwords which are close to your model of laptop.

Try the codes on the locked BIOS message to see if it works, depending on laptop models you may need to press Enter or Ctrl+Enter after entering the code. The codes used are based on the work of “Dogbert” who’s done a lot of research and created a number of small utilities and also Python scripts for unlocking several different brands of laptop.

If the website above or its codes don’t work, visit Dogbert’s Blog where you will be able to find more details about your laptop brand and download a separate master password utility for it. To use one of the programs, simply download the correct one for your laptop and run it, then type in the number and hit enter. The master password will be displayed for you to try and unlock the computer.

You have to run the master password tool on a computer that can boot into Windows and has .NET installed. If you don’t know which tool to use, it’s safe to try all of them until you find the one that matches your laptop.

My BIOS password is fine but hackers changed access level to user and created a user password that I can’t figure out. They also partitioned my C drive and moved everything to that new file. I need to get access to CMOS using a DOS command if possible. Using the boot drive they created, which is no longer full of theyre crap, I can access Windows dir. Is there any way to changeable CMOS user info through the commands?

My understanding of your problem is you have a user account you cannot access and your partitions are not setup properly. This has nothing to do with CMOS, however. Using a boot disk for another operating system, backup all of your personal files, reinstall windows and then restore your personal files. There are several tricks you can use to gain user access to the system, the most notable being the sticky keys method. If sticky keys is enabled on your machine this should work. First, go to the system32 directory in the windows system files, from an OS boot disk where you can access the windows drive. you have to rename the sethc.exe to something else (Dont delete it) and then make a copy of cmd.exe and rename it to sethc.exe. Once this is done boot into windows and press shift 5 times to bring up a console, where you can use the net user command to create a new user or change the password.

WARNING: Some BIOS configurations will lock you out of the system completely if you type in an incorrect password more than 3 times. Read your manufacturers documentation for the BIOS setting before you begin typing in passwords.

Lenovo T460s has a Supervisor password (unknown) and the CMOS battery had also died. Obviously now I am being prompted for basic time date etc but cannot change anything because I don’t have the Supervisor Password. I have been told by several people that I am up for another motherboard – is this true – is there no other option here … that is crazy!

leave cmos battery out, take battery off leave for half an hour to an out with no power then put coms battery in the main battery in and boot should have no password then. work 65% of the time some time batteries need to be out longer.

​finally i found easy solution how to remove bios password without any program and i wrote it on acer page you can guys see there:
community.acer.com/t5/Legacy-Laptops-and-Netbooks/acer-aspire-unlocked-bios/m-p/429008#M68532

hi there: after Reading a lot of web pages, I´m at a dead end. My vaio laptop has a bios password and, if I type the passoword three times wrong, appears one time password, then three times wrong again, appears “system disabled” but without any number.
What can I do?
Thanks!

After a long study of these solutions and a scouring of the internet, I have concluded that there is no solution for the newer laptops such as the Dell Latitude E5520. None of the code-generators nor the bios-flashing applications work on these.

I have a Lenovo Ideapad Z560 with InsydeH2O Bios and I have forgot its Bios Password, which was set four years ago. I cannot login to the windows because it is corrupted. But I can select the boot device priority from the bios by pressing F12 Key.There is no alphanumeric code displayed, when password is wrongly entered. Is there any way to flash this bios and remove its password? I tried several methods, and fed up with all of the methods. Can you please help me?

i have an asus notebook with a bios password problem i tried the cmos battery removal..didn’t work, tried to disassemble the notebook…didn’t work it still ask for a password, went to geek squad they say buy a new notebook…is there really no way to over the bios password?

If none of the methods here work, a last resort would be to try and get another BIOS EPROM chip but not all laptops allow for this and it depends if your laptop uses two chips for the BIOS/CMOS or one.

Thanks for posting this nice lesson on your site.I was able to unlock my Acer laptop by reading and following the instruction on you website.At first,I though youtude could have help me but I tried as much I could and nothing like help I was able to get.But unfortunately,I was able to reach you site and my problems were able to be solved. Thanks

I’m having Bios issues , my laptop screen displays Service Tag and requests System or Administrator password… My Bios doesn’t support Cd and flash options… I’ve tried removing the Cmos and resetting the Jumper.. Tried all the master passwords.. Still no luck.. And most of all the engineers here can’t fix it… The ones who claim they can are charging a fee too high or half the price of getting a Used laptop.. Its a Dell vostro 1540

Raymond, You Really Rock!!!!! Thanks a lot Bro, now i can reset the BiOS password of my laptop. It was so annoying before, but since you have told me about it, no more words anymore but YOU ROCK!!! again, thanks a lot Raymond!
Regards – Amirz